Over the years various sealing arrangements have been designed to seal the annular shrouds surrounding the tips of turbine blades. Feather seals are typically installed in the aft and forward rails of the shroud support structures to minimize cooling air leakage through the shroud segments.
A main disadvantage of such feather seals is that it provides for a multi-part sealing arrangement (e.g. 12–24 feather seals) which renders the assembly procedure more complex, thereby resulting in extra costs. Furthermore, feather slots must be machined in each shroud segments for allowing the feather seals to be positioned in the aft and forward rails of the outer shroud support, which further increases the manufacturing cost of the engine. Finally, such a multi-part sealing arrangement contributes to increase the overall weight of the gas turbine engine.